Add unit test to compare library against Top 4 GitHub TOTP libraries

Author: marcelkliemannel

build.gradle.kts

@@ -1,5 +1,4 @@
 import java.net.URI
-import kotlin.math.sign
 
 plugins {
   `java-library`
@@ -61,6 +60,16 @@ dependencies {
   testImplementation("org.junit.jupiter:junit-jupiter-params:$jUnitVersion")
   testImplementation("org.junit.jupiter:junit-jupiter-api:$jUnitVersion")
   testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:$jUnitVersion")
+
+  testImplementation("com.github.bastiaanjansen:otp-java:1.3.0") {
+    because("For `OtherLibrariesComparisonTest`")
+  }
+  testImplementation("com.eatthepath:java-otp:0.3.1") {
+    because("For `OtherLibrariesComparisonTest`")
+  }
+  testImplementation("com.j256.two-factor-auth:two-factor-auth:1.3") {
+    because("For `OtherLibrariesComparisonTest`")
+  }
 }
 
 tasks.withType<Test> {

src/test/kotlin/dev/turingcomplete/kotlinonetimepassword/OtherLibrariesComparisonTest.kt

@@ -0,0 +1,74 @@
+package dev.turingcomplete.kotlinonetimepassword
+
+import com.bastiaanjansen.otp.HMACAlgorithm
+import com.bastiaanjansen.otp.TOTP
+import com.j256.twofactorauth.TimeBasedOneTimePasswordUtil
+import org.apache.commons.codec.binary.Base32
+import org.junit.jupiter.api.Assertions
+import org.junit.jupiter.api.DisplayName
+import org.junit.jupiter.params.ParameterizedTest
+import org.junit.jupiter.params.provider.CsvSource
+import java.time.Duration
+import java.time.Instant
+import java.util.concurrent.TimeUnit
+import javax.crypto.spec.SecretKeySpec
+
+class OtherLibrariesComparisonTest {
+  // -- Companion Object -------------------------------------------------------------------------------------------- //
+
+  companion object {
+    private val SECRET_PLAIN = "#ug0sEABk,}@anh&<ozWM6,#Nq/<NC3s"
+    private val SECRET_BASE_32 = Base32().encodeToString(SECRET_PLAIN.toByteArray()).toString()
+  }
+
+  // -- Properties -------------------------------------------------------------------------------------------------- //
+  // -- Initialization ---------------------------------------------------------------------------------------------- //
+  // -- Exposed Methods --------------------------------------------------------------------------------------------- //
+
+  @ParameterizedTest
+  @DisplayName("com.eatthepath:java-otp (https://github.com/jchambers/java-otp)")
+  @CsvSource(value = ["15, 6", "15, 8", "30, 6", "30, 8", "45, 6", "45, 8"])
+  fun testComparetoEtthapath(timeStepSeconds: Long, digits: Int) {
+    val currentTime = System.currentTimeMillis()
+    val expectedCode = createExpectedCode(timeStepSeconds, digits, currentTime)
+
+    // Library only supports 6-8 digits
+    val eatthepath = com.eatthepath.otp.TimeBasedOneTimePasswordGenerator(Duration.ofSeconds(timeStepSeconds), digits, com.eatthepath.otp.TimeBasedOneTimePasswordGenerator.TOTP_ALGORITHM_HMAC_SHA1)
+    val eatthepathCode = eatthepath.generateOneTimePasswordString(SecretKeySpec(SECRET_PLAIN.toByteArray(), "RAW"), Instant.ofEpochMilli(currentTime))
+    Assertions.assertEquals(expectedCode, eatthepathCode)
+  }
+
+  @ParameterizedTest
+  @DisplayName("com.github.bastiaanjansen:otp-java (https://github.com/BastiaanJansen/otp-java)")
+  @CsvSource(value = ["15, 6", "15, 8", "30, 6", "30, 8", "45, 6", "45, 8"])
+  fun testCompareToBastiaanJansen(timeStepSeconds: Long, digits: Int) {
+    val currentTime = System.currentTimeMillis()
+    val expectedCode = createExpectedCode(timeStepSeconds, digits, currentTime)
+
+    // Library only supports 6-8 digits
+    val bastiaanjansen = TOTP.Builder(SECRET_BASE_32.toByteArray()).withAlgorithm(HMACAlgorithm.SHA1).withPasswordLength(digits).withPeriod(Duration.ofSeconds(timeStepSeconds)).build()
+    val bastiaanjansenCode = bastiaanjansen.at(Instant.ofEpochMilli(currentTime))
+    Assertions.assertEquals(expectedCode, bastiaanjansenCode)
+  }
+
+  @ParameterizedTest
+  @DisplayName("com.j256.two-factor-auth:two-factor-auth (https://github.com/j256/two-factor-auth)")
+  @CsvSource(value = ["15, 6", "15, 8", "30, 6", "30, 8", "45, 6", "45, 8"])
+  fun testCompareToJ256(timeStepSeconds: Long, digits: Int) {
+    val currentTime = System.currentTimeMillis()
+    val expectedCode = createExpectedCode(timeStepSeconds, digits, currentTime)
+
+    val j256Code = TimeBasedOneTimePasswordUtil.generateNumberString(SECRET_BASE_32, System.currentTimeMillis(), timeStepSeconds.toInt(), digits)
+    Assertions.assertEquals(expectedCode, j256Code)
+  }
+
+  // -- Private Methods --------------------------------------------------------------------------------------------- //
+
+  private fun createExpectedCode(timeStepSeconds: Long, digits: Int, currentTime: Long): String {
+    val config = TimeBasedOneTimePasswordConfig(timeStep = timeStepSeconds, timeStepUnit = TimeUnit.SECONDS, codeDigits = digits, hmacAlgorithm = HmacAlgorithm.SHA1)
+    val generator = TimeBasedOneTimePasswordGenerator(SECRET_PLAIN.toByteArray(), config)
+    return generator.generate(currentTime)
+  }
+
+  // -- Inner Type -------------------------------------------------------------------------------------------------- //
+}